Radial cooling system for casting wheel



May 16, 1967 Filed Feb. 12, 1965 WI/Ill T. 1.. BRAY ETAL 3,319,700

RADIAL COOLING SYSTEM FOR CASTING WHEEL 3 Sheets-Sheet 1 INVENTORSTHOMAS L. BRAY GEORGE C WARD 91 wad 7" ATTORNEYS May 16, 1967 T. L. BRAYETAL 3,3

RADIAL COOLING SYSTEM FOR CASTING WHEEL Filed Feb. 12, 1965 5Sheets-Sheet 2 INVENTORS THOMAS L. BRAY GEORGE c. WARD 4r" ATTORNEYS May16, 1967 T. BRAY ETAL 3,319,790

I RADIAL COOLING SYSTEM FOR CASTING WHEEL Filed Feb. 12, 1965 5Sheets-Sheet 3 INVEN'TORS THOMAS L. BRAY GEORGE C. WARD druab ATTORNEYSUnited States Patent 3,319,700 RADIAL COOLING SYSTEM FOR CASTING WHEELThomas L. Bray, Birmingham, Ala., and George C. Ward, Carrollton, Ga,assignors to Southwire Company, Carrollton, (3a., a corporation ofGeorgia Filed Feb. 12, 1965, Ser. No. 432,211 12 Claims. (til. 164-283)This invention relates generally to the continuous casting of metal andmore particularly to a cooling system for cooling a casting wheel whichis used in the continuous casting of metal.

The casting of metal in a peripheral groove around a rotating wheel, thegroove being closed by an endless belt encircling a portion thereof, iswell known in the casting art. One of the critical problems involvedwith this type of casting is the uniform cooling of the liquid metalwhile confined within the casting groove. Generally, two methods ofcooling have been used on this type casting wheel: spray cooling andchannel cooling.

Spray cooling has provided an easily controllable means for cooling themetal within the groove of an annular casting ring; however, this typeof cooling has several drawbacks. One of its drawbacks is that, sincethe spray is made to impinge at spaced intervals on the outside surfaceof the casting ring, the casting ring must be made as thin as possiblein order to provide the best conduction of heat therethrough. Thisparticular construction, however, results in greatly reduced strength ofthe annular casting ring, thereby allowing the metal of the casting ringto be easily deformed under the extremely high temperatures to which itis subjected. Another drawback is that cooling has been non-uniformbecause the heat transferred is greatest at the points of impingement ofthe stream of coolant against the casting ring, since at these positionsthe coolant is in contact with the casting ring. It is readilyunderstood that, as points on the ring move between positions wherecoolant sprays are located, less coolant is in contact with the ring.This has caused hot and cold spots along the casting ring which resultsin inefficient cooling.

Channel cooling of annular casting rings has usually been done witharcuately extending channels formed inwardly of the periphery of acasting ring, and adjacent to a casting groove. This has required thatthe casting ring be made of relatively thick wall sections in order toprovide the necessary strength for proper support of the metal withinthe casting groove, and has also resulted in non-uniform cooling of themetal bar formed within the casting ring. In usual practice, the coolantis relatively cool when first introduced into the coolant channels, butas the coolant flows along the circular path of the coolant channels itpicks up heat dissipated from the molten metal that is confined withinthe casting ring. As the coolant is heated, the heat transfer ratedecreases due to the decrease in temperature difference; and, the liquidcoolant thereby produces a varying cooling rate at different pointsalong the length of the coolant channel. Therefore, even it severalshort lengths of cooling channels were used around the casting ring, thecooling rate would vary along the length of each cooling channel.

The present invention overcomes these and other problems associated withprevious cooling systems for casting rings by providing a plurality ofradially extending channels which allow substantially uniform cooling ofthe casting ring along the length of the casting groove at all times.The cooling system of the present invention possesses the advantages of:

(1) Uniform cooling along segments of the length of cast metal since thecoolant is introduced at closely spaced intervals positioned on radii ofthe casting ring 3,3193% Patented May 16, 1967 thereby producing moretotal coolant ring contact time in a given zone;

(2) Minimizing the path of travel of each individual coolant channel,thereby producing a maximum heat transfer differential at each positionof coolant introduction; and,

(3) Flexibility in controlling the rate of coolant flow to establishstaged cooling zones.

The apparatus of the invention comprises a casting ring having radiallyextending coolant channels formed therein so that the coolant contactsthe casting ring at a relatively short distance from the outer surfaceof the casting groove as the coolant is caused to flow through theradially extending channels in the casting ring, and along a very smallincrement of the length of the groove. Coolant is introduced into thechannels by a plurality of radially extending nozzles disposed adjacentthe inner surface of the casting ring which also force coolant along theradially extending sectional channels. The particular arrangement of thenozzles can be easily varied so that different uniform rates of coolingcan be produced in different zones of the casting ring if that should bedesired.

These and other features and advantages of the present invention willbecome apparent from consideration of the following detailed descriptiontaken in conjunction With the accompanying drawings wherein likecharacters of reference designate corresponding parts throughout and inwhich:

FIG. 1 is an elevational view of a casting machine utilizing anembodiment of the invention;

FIG. 2 is a cross-sectional View of a casting ring embodying theinvention;

FIG. 3 is a cross-sectional view of the casting ring shown in FIG. 2,removed from its associated structure;

FIG. 4 is a cross-sectional view of a second embodiment of the presentinvention;

FIG. 5 is an enlarged sectional view of a portion of the secondembodiment of the invention shown in FIG. 4, partially broken away toillustrate the position of the cooling channels within the casting ring;

FIG. 6 is a schematic illustration showing a cooling manifold and nozzlearrangement for zoned cooling that can be utilized in the presentinvention; and

FIG. 7 shows a means for rotating the cooling manifold shown in FIG. 4.

Referring now particularly to the detailed drawings, it will be seenthat FIG. 1 illustrates a casting machine in which the invention isembodied. It is to be understood, however, that the invention is notlimited in any way by the details disclosed herein since it may beembodied in other equivalent forms.

The casting machine has a casting wheel 10, a frame 11 rotatablysupporting the casting wheel 10 and an endless belt 12 encircling aportion of the casting wheel 10. The periphery of the casting wheel 10carries the casting ring 14 wherein the invention is embodied.

Referring to FIGS. 2 and 3, the first embodiment of the invention isseen to comprise a disc shaped mounting plate 15 which is integral with,and extends perpendicularly outward from a support shaft 13, the shaft13 bemg rotatably journaled in a frame 11. A retaining annulus 18 hasthe same diameter as the support plate 15 and is spaced from the supportplate 15 so that their axes of rotation coincide. An annular castingring 14 is retained between the support plate 15 and the annulus 18 inappropriate annular slots 19 which are formed in the inner faces of thesupport plate 15 and the annulus 18. A plurality of bolts 16 extendthrough the support plate 15, the casting ring 14 and the annulus 18 tohold the assembly together to form the casting wheel 10.

The casting ring 14 defines a casting groove 20 in its outer peripheralsurface 20a, and has transverse, outwardly extending lips 21 adjacentthe mouth of the groove 20, the lips 21 being received by the slots 19that are provided in the support plate 15 and the annulus 18. Two narrowcoolant channels 24 extend radially inwardly from beneath the lips 12 ofthe casting ring 14 adjacent the inner surface 20a of the casting groove20, and converge at a point along a radius of the casting ring 14 wherethe coolant is introduced. A plurality of these channels 24 are formedat closely spaced intervals about the circumference of the casting ring14. The outer ends of the coolant channels 24 terminate immediatelybelow the outwardly extending lips 21 of the casting ring 14; and, thecoolant is returned inwardly through the return channels 25 whichcommunicate with the channels 24. This allows coolant to be introducedinto the cooling channels 24, to flow along the channels 24 adjacent thecasting groove 20 while removing heat conducted from the molten metalthrough the casting ring 14, and to exit inwardly toward the center ofthe casting wheel along the channels 25. It is to be understood that, inorder for the casting ring 14 to retain its proper strength, thechannels 24 must have a narrow width and be spaced far enough apart sothat support webs 24 between the channels 24 provide enough strength tokeep the casting ring 14 from warping or otherwise deteriorating whenhot, molten metal is poured within the casting groove 20.

Referring to FIGS. 4 and 5, the second embodiment of the invention isseen to comprise a disc shaped mounting plate 15 integral with andextending perpendicularly outward from a support shaft 13. A retainingannulus 18' has the same diameter as the support plate 15' and is spacedfrom the support plate 15' so that their axes of rotation coincide. AU-shaped, removable mold portion 26 is retained between the supportplate 14 and the annulus 18 in appropriate annular slots 19' which areformed in the inner faces of the support plate 15 and the annulus 18'. Asupport member 28 is also carried between the support plate 15' and theannulus 18' by bolts 16, and serves to support the removable moldportion 26. The entire wheel assembly 10 is rotatably carried by a frame11 in which the support shaft 13 is journaled.

The removable mold member 26 defines a casting groove 20, and haslateral, outwardly extending lips 21' adjacent the mouth of the groovethe lips being received by the slots 19 provided in the support plate15' and the annulus 18. A plurality of set screws 23 serves to retainthe lips 21' of the removable mold portion 26 in the slots 19.

The support member 28 is mounted so that its outside surface iscontinuous with the inside surface of the removable mold portion 26 byproviding a recess 27 in which the removable portion 26 rests. Thesupport member 28 comprises two mating sections 28a and 2812 so that thesupport member 28 can be assembled around the base portion of theremovable mold portion 26. For the sake of simplicity however, in thefollowing description of the support member 28, it will be referred toas a single element. The removable mold portion 26 has coolant channels44, each of which is formed inwardly of the recess 27 along a givenradius of the support member 28 and opens into the recess 27. Aplurality of these channels 44 are formed at closely spaced intervalsabout the circumference of the support member 28. An inlet port 45extends inwardly of the innermost point of each of the channels 44,through the support member 28, and opens on the inner surface of thesupport member 28; therefore, coolant can be introduced into thechannels 44 and flow radially outward, while remaining in contact at alltimes with the inside surface of mold portion 26. Return channels 30extend radially inward from the outermost extending ends of the channels44.

Several forms for supplying coolant to the channels 44 can be used,three of such forms being shown herein 4 in FIGS. 4, 6 and 7; and, allinclude means within the cavity defined by the support plate 15', theannulus 18' and the support ring 28 of the second embodiment of theinvention.

Referring to FIGS. 4 and 5, a first form of coolant introductory meansis shown which comprises a coolant manifold 32 having outwardlyextending nozzles 34 aligned with the ports 45 in the support member 28for Y spraying coolant into the channels 44. The coolant manifold 32communicates with a coolant supply pipe 35 which has a valve 36 thereinfor regulating the flow of coolant through the pipe 35, the manifold 32and hence the channels 44 in the support member 28. Therefore,regulating the valve 36 will vary the flow of coolant through thechannels 44, hence the rate of heat transferred from any metal that maybe within the casting groove 20.

Referring now to FIG. 6, a second form of introductory means is shownproviding zoned cooling. The only necessary changes in the firstembodiment of the introductory means are in the coolant manifold 32which is shown as a coolant manifold 32 in FIG. 6. Any number of coolingzones can be provided in the introductory means, but only three suchcooling zones A, B and C are shown in the embodiment of FIG. 6. Thecoolant manifold 32 is stationary within the cavity formed in the wheelassembly, with a first zone A having a plurality of closely spacednozzles 34 extending from the coolant manifold 32 so as to introduce alarge volume of coolant into the channels 44. As is shown in FIG. 6, thezone A is usually placed adjacent to support ring 28, beginning at thatpoint of the mold portion 26 which receives the liquid metal. A secondzone B is provided by a plurality of nozzles 34', which are spaced agreater distance apart than those nozzles 34' in zone A. As seen in FIG.6, the cooling zone B is spaced clockwise from, and adjacent to, zone A.These nozzles 34' of zone B are usually spaced a distance further apartthan those of zone A, since the metal is substantially solid by the timeit passes through zone A, and less heat transfer is needed. Zone Busually extends clockwise around the manifold 32 to that point on themold portion 26 at which the solidified metal bar is extracted from thecasting groove 20. Extending from the end of zone B, clockwise aroundthe manifold 32 to the beginning of zone A, is the cooling zone C whichis provided by a plurality of nozzles 34, the nozzles 34' being spaced agreater distance apart than either those of zone A or those of zone B.Since the solodified metal bar has been extracted from the castinggroove during the time the support member 28 is adjacent the coolingzone C, less flow of coolant is needed than in zones A and B since thecasting groove is open and free from contact with the molten metal.Thus, it is seen that zone A provides the greatest cooling capacity forthe liquid metal, zone B provides a lesser cooling capacity than zone A,and zone C provides the least cooling capacity of the three zones A, Band C. It will be further seen that more or fewer cooling zones can beprovided by the nozzles 34 as required to solidify the liquid metalinjected into the casting groove 20 and to cool this solidified bar to adesired temperature before the bar is extracted from the casting groove20.

Referring now to FIG. 7, a third embodiment of the introductory means isshown. This embodiment uses an independently rotatable manifold 32". Thecoolant manifold 32" has the same general construction as the coolantmanifold 32, but is rotatably journaled in a support stand 40 so thatthe manifold 32" can be rotated in the direction of rotation of thecasting wheel 10, or in the opposite direction of rotation from thecasting wheel 10. A coupling 42 is provided at the end of a support tube43 so that water can be introduced into the coolant manifold 32" via thesupport tube 43. The flow of coolant in this third form of theintroductory means is controlled by the valve 36 as shown in FIG. 1.With this form, a more nearly uniform flow of coolant will be introducedagainst the outside surface of the removable mold portion 26 through thechannels 44 since the outimum speed relationship can be achieved byrotating the manifold 32" in the proper direction and speed no matterwhat the rotational speed of the wheel may be. This optimum speedrelationship is that speed relationship at which maximum coolingefiiciency takes place; therefore, the maximum cooling efiiciency can beachieved regardless of the rotational speed of the support ring 28.

It will be obvious to those skilled in the art that many variations canbe made in the embodiments herein chosen for illustration withoutdeparting from the scope of the invention as defined by the appendedclaims.

I-claim:

1. In a casting machine, a casting ring having in its peripheral surfacea casting groove and having formed therein a plurality of separate firstchannels each of which extends adjacent said casting groove frominwardly of said casting groove substantially to said peripheral surfaceand each of which is along its length substantially equi-distant fromsaid casting groove, means for positioning said casting ring forrotation about an axis and for providing with said casting ring aplurality of second channels each of which is continuous with one ofsaid first channels and extends inwardly toward said axis, and meanspositioned inwardly of said casting groove for flowing coolant throughsaid first channels and said second channels.

2. The casting machine of claim 1 in which each of said first channelsextends radially outward toward said peripheral surface.

3. The casting machine of claim 2 in which each of said second channelsextends radially inward away from said peripheral surface.

4. The casting machine of claim 1 in which said means positionedinwardly of said casting groove includes a plurality of ports in saidcasting ring continuous with said first channels, a plurality of nozzlesadjacent said ports, and means for providing said coolant to saidnozzles.

5. The casting machine of claim 4 in which said ports move relative tosaid nozzles.

6. The casting machine of claim 4 in which said nozzles are spaced alongthe inner periphery of said casting ring.

7. The casting machine of claim 6 in which the spacing between saidnozzles varies.

8. The casting machine of claim 1 in which said casting ring includes asupport member having a recess and a mold portion defining said castinggroove positioned in said recess.

9. The casting machine of claim 8 in which said first channels areformed between said support member and said mold portion.

10. The casting machine of claim 8 in which said support member includesseparable mating sections having said mold portion positioned betweenthem.

11. In a casting machine having an annular mold portion rotatable aboutan axis, a cooling system comprising an annular support member shaped toreceive said mold portion and having a plurality of radially extendingchannels therein opening against said mold portion so that coolantflowing through each of said channels is confined on one side by saidsupport member and on the other side by said mold portion, means forintroducing coolant into said channels, said means comprising a circularcoolant manifold rotatable about said axis of said mold portionindependently of said mold portion and having outwardly extendingnozzles around the periphery thereof, and valve means for judiciouslyregulating the flow of coolant through said nozzles.

1.2. In a casting machine having an annular mold portion rotatable aboutan axis, a cooling system comprising an annular support member shaped toreceive said mold portion and having a plurality of radially extendingchannels therein opening against said mold portion so that coolantflowing through each of said channels is confined on one side by saidsupport member and on the other side by said mold portion, and means forintroducing coolant into said channel comprising a circular coolantmanifold rotatable about said axis of said mold portion independently ofsaid mold portion and having a plurality of equally-spacedcoolant-discharging nozzles around the periphery thereof disposedadjacent entrances of said channels, and driving means for rotating saidcoolant manifold.

References Cite-d by the Examiner UNITED STATES PATENTS 368,817 8/1887Daniels 2257 X 944,370 12/ 1909 Monnot 2257.2 1,870,406 8/1932 Douteur2257.4 2,865,067 12/1958 Properzi 2257.4

FOREIGN PATENTS 73,578 6/1953 Netherlands. 89,511 5/1957 Norway. 861,2732/-1961 Great Britain.

WILLIAM J. STEPHENSON, Primary Examiner.

R. S. ANNEAR, Assistant Examiner.

1. IN A CASTING MACHINE, A CASTING RING HAVING IN ITS PERIPHERAL SURFACEA CASTING GROOVE AND HAVING FORMED THEREIN A PLURALITY OF SEPARATE FIRSTCHANNELS EACH OF WHICH EXTENDS ADJACENT SAID CASTING GROOVE FROMINWARDLY OF SAID CASTING GROOVE SUBSTANTIALLY TO SAID PERIPHERAL SURFACEAND EACH OF WHICH IS ALONG ITS LENGTH SUBSTANTIALLY EQUI-DISTANT FROMSAID CASTING GROOVE, MEANS FOR POSITIONING SAID CASTING RING FORROTATION ABOUT AN AXIS AND FOR PROVIDING WITH SAID CASTING RING APLURALITY OF SECOND CHANNELS EACH OF WHICH IS CONTINUOS WITH ONE OF SAIDFIRST CHANNELS AND EXTENDS INWARDLY TOWARD SAID AXIS, AND MEANSPOSITIONED INWARDLY OF SAID CASTING GROOVE FOR FLOWING COOLANT THROUGHSAID FIRST CHANNELS AND SAID SECOND CHANNELS.